The present disclosure relates to grippers for electrical or optical lines such as wires, cable, line bundles, optical fibres; to twisting heads for the twisting of such electrical or optical lines; as well as to twisting apparatus for the twisting of such electrical or optical lines.
A typical configuration of such a gripper has at least one gripper jaw that can be moved relative to a counterbearing by means of a drive arrangement. Preferably provided are two gripper jaws that may be moved relative to one another. Such gripper is used in twisting heads that are typically provided in twisting apparatus for example, for wires, cables, line bundles, optical fibres etc., and at the same time can be rotated by at least one drive.
DE 1 0201 001 7981 A1 discloses a device for combining conductors to produce a double crimp connection. The (double) grippers used therein possess gripper arms held in a guide, which are displaceable vertically to the gripper plane.
EP 1032095A1 relates to processing and twisting of a pair of conductors. The grippers as a whole are individually pivotable by a lever mechanism associated with a pivoting unit. However, the gripping of the wire is not accomplished by the lever mechanism shown.
EP 1691457A1 discloses an untwisting unit associated with a cable processing device. A gripper is driven pneumatically (for example, closed pneumatically and opened by means of spring force).
U.S. Pat. No. 4,272,951A discloses a twisting apparatus in which the twisting is accomplished by a roller or belt arrangement that embraces the wires to be twisted from two sides. In this case, these rollers or belt arrangement may be twisted. A completely different principle is involved in this reference.
U.S. Pat. No. 5,605,181A discloses a portable twisting tool wherein the wires to be twisted are clamped by an apparatus at the centre of their length. At their ends the wires are fixed stationarily by fastening devices. The twisting apparatus consists of a sleeve having an elongated cut-out into which a part is inserted which sits on a second sleeve and projects between the two wires.
DE 10107670A1 discloses a twisting head having three gripper jaws that can be moved relative to a counterbearing, and that are opened or closed via a mechanical link chain by a drive in the form of a fluidic working cylinder. In this case, the gripper jaws move with their front end radially in relation to the line to be clamped, whereas the drive acts predominantly parallel to the line.
All the solutions known in the prior art have in common that they are mechanically complex and have a high weight. Twisting apparatuses are therefore very expensive, and the drive requirement is high. In addition, the holding force for line ends is not adjustable.